Contact lenses, which are to be manufactured economically in large unit numbers, are preferably manufactured by the so-called mould or full-mould process. In these processes, the lenses are manufactured into their final shape between two moulds, so that there is no need to subsequently finish the surfaces of the lenses, nor to finish the edges. Such moulds consist of a female mould half and a male mould half, the cavity being formed between the two mould halves defining the shape of the moulding. Mould processes are described for example in PCT application no. WO/87/04390 or in European patent application EP-A-0 367 513.
In these known mould processes, the geometry of the contact lenses to be manufactured is defined by the mould cavity. The edge of the contact lens is likewise formed by the mould which normally consists of two mould halves. The geometry of the edge is defined by the contour of the two mould halves in the area in which they touch one another.
It is to the provision of a meeting these and other needs that the present invention is primarily directed.